Recoil absorbing mechanism for firearms



Jan. 30, 1962 v. A. BROWNING RECOIL ABSORBING MECHANISM FOR FIREARMSFiled May 7, 1959 5 R Y Q\ m m W Q l E o N f/ mm w w N A a w W 4% o w/ mM A M L m absorbing mechanism of 3,018,694 RECGIL ABSORBING MECHANISMFOR FIREARMS Val A. Browning, Ogden, Utah, assignor to BrowningIndustries, Inc., Ogden, Utah, a corporation of Utah Filed May 7, 1959,Ser. No. 811,699 8 Claims. (Cl. 89-159) This invention relates tofirearms and is concerned, more particularly, with a recoil absorbingmechanism for repeating firearms of the automatic or semi-automatic t e.

The invention is adapted for use with firearms of the type wherein thebarrel or a portion of the barrel is mounted for reciprocation relativeto a frame and will recoil relative to the frarne when the gun is fired,which recoil movement may be used to perform the automatic functioningof the piece, such as ejection of the expended round, cocking the firingmechanism and reloading the firing chamber.

An aim of the present invention is to provide a recoil relatively lightWeight which will obviate the need for heavy springs, friction devicesand the like, and which at the same time will function reliably anduniformly to decelerate and halt the rearward movement of the barrelmember in such manner that violent or sudden impact or kick is greatlyreduced. Included in this aim is the provision of a recoil mechanism ofthis type which can be made to operate in a so-called short-recoilsystem and wherein the mechanism requires no adjustment for use withvarying loads.

Another aim is to provide such a recoil absorbing mechanism which iseconomical to manufacture and yet which is durable and rugged inoperation, and which will not detract from the good balance or feel andappearance of the firearm.

In the drawings:

FIG. 1 is a fragmentary side view, partially in section, of asemi-automatic, recoil-operated firearm embodying the present invention;

FIG. 2 is a cross-secitonal view taken along the line 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken along the line 33 of FIG. 1;

FIG. 4 is a perspective view of the piston member; and

FIG. 5 is a perspective view of the end portion of the magazine tube inwhich the piston member is slidably mounted.

Referring to the drawing, the invention has been shown as embodied in afirearm which is a semi-automatic shotgunof the type disclosed andclaimed in my prior Patent No.2,499,090 issued February 28, 1950, towhich reference may be had for additional details which are notspecifically described here. The shotgun comprises a receiver or frame2, a barrel 4 provided with a barrel extension 3 mounted forreciprocation in the receiver, and a breech block 5 for locking acartridge in the firing chamber. Extending forwardly from the frame 2beneath the barrel 4 is a magazine tube 8 fixed to the frame 2 andenclosed by the usual wooden forearm 6.

Forwardly of the receiver 2 and preferably at about midlength of thebarrel 4 is a downwardly depending guide ring 10 on the barrel whichencircles the magazine tube 8 and is slidable thereon. A lightcompression spring 12 encircling the magazine tube 8 is seated at oneend in the forearm 6 and at its other end operates against guide ring10, biasing it forwardly. A threaded cap 14 closes the outer end of themagazine tube 8.

A disc 16 is brazed or otherwise mounted in the magazine tube 8rearwardly of the ring 10 to divide it into lifilfifigd Patented Jan.30, 1962 a rearwardly disposed magazine section 18 with its magazinespring 20, and the air cylinder section 22. A reinforcing band 24 isdesirably provided about the magazine tube 8 at the location of the disc16 and a reinforcing metal liner 26 is shown between the tube 8 andforearm 6. A piston 28 is slidably carried in the air cylinder section22 of the magazine tube 8, and is provided with a gas sealing element orpiston ring 30 adjacent its rear face, such as an expanding steel ring.Carried in the forward face of the piston 28' is a buffer 32,conveniently of wood, which abuts the cap 14. The piston 28 is attachedto the ring 10 for reciprocal movement with the ring and the barrel 4 bymeans of a pin 34 which is inserted through the transverse hole 33 inthe piston and engages in holes 35 in the guide ring, the pin extendingthrough the lateral slots 36 of the tube 8. The slots 36 are of asufficient length to accommodate the reciprocal movement of the piston28 with the barrel 4. However, the piston 28 is of greater length thanthe slots 36 so that the piston seals the air chamber from theatmosphere.

To conduct gases from the interior of the barrel 4 to the air cylinder22 there is provided a port 38 bored upwardly through the guide ring 10and an elongated slot 40 in the top of the tube 8. A gas passage throughthe piston 28 is comprised of an axial bore 42 extending from the rearface of the piston to an upwardly extending bore 44 which registers withthe port 38. As illustrated in FIG. 1, the spring 12 biases the piston28 and barrel 4 forwardly so that when the piece is in battery, the port38 and bore 44 are forward of the slot 40 and thus are separated by thesolid portion of the tube 8. However, When the piece is fired, thebarrel 4 recoils rearwardly with simultaneous movement of the piston 28,so that the gas passages 38 and 4 1 are in registry with the slot 4%during a portion of the rearward movement. During the final stage ofrecoil when the barrel 4 and piston 28 have moved rearwardly to aposition where the passages 38 and 44 are beyond the rear end of theslot 40, the communication between passages 38' and 44 is again closedby the solid portion of tube 8. In short, the tube 8 with its slot 40functions as a valve controlling the flow of gases between passages 38and 44.

The operation of the recoil absorbing mechanism of the present inventionwill be readily understood from the foregoing description taken with thefollowing explanation. When a shot is fired, the projectile or shotcharge is propelled forwardly and the barrel recoils rearwardly carryingwith it the piston 28. 'At this stage,

the recoil is resisted principally by the very light return spring 12 sothat very little force or kick is transferred to the frame or receiver2. This initial recoil movement will be sufficient to move passages 38and 44 into registry with the slot 40 so that after the projectile orshot charge passes the part of the barrel containing the port or passage38, the gases of combustion under high pressure hehind the projectile orshot charge will bleed through the passages 38, 44 and 42 to the rear ofthe piston 28 and into the cylinder 22, thus rapidly increasing thefluid pressure behind the piston 28 and initiating a progressive slowingdown of the recoil movement. With the passage 38 located approximatelymidlength of the barrel or at a somewhat lesser distance from thebreech, the conditions of gas pressures and timing of the admission ofgases to the cylinder 22 appear to be most favorable to produce thedesired recoil absorbing action. As will be apparent to one skilled inthe art, the distance of recoil of the barrel before the projectile orshot passes the port 38 will vary with the load but although the barrel4 and accompanying piston 28 move rearwardly a greater distance as aresult of a larger load, the gas pressure in the barrel behind the shotor projectile will be corresponding greater and thus gas under higherpressure will enter the cylinder 22 to automatically increase the recoilabsorbing action and compensate for the greater recoil velocity. Theslot 40 is made sufiiciently long so that communication between passages38 and 44 is established when the projectile or shot passes the passage38 regardless of variations in distance of recoil due to variations ofload. By way of specific example, in the specific embodiment shown therecoil movement of the barrel may vary from approximately .2 to .7 inchin the time that the shot reaches the port 38 depending on the load, andthus a slot 40 having a length of approximately .9 inch will be adequateto cover the entire range.

As the barrel continues to recoil and after there has been aconsiderable build up of fluid pressure behind the piston 28, thepassages 38 and 44 are carried beyond the end of the slot 40, thusclosing the entrance to the cylinder 22. This occurs just shortly beforethe projectile or shot leaves the muzzle so that even though there is asubsequent rapid reduction in the gas pressure in the barrel, the highgas pressure in the cylinder 22 is maintained. Thus during thesubsequent final recoil movement of the barrel which may beapproximately 30% of the entire recoil movement, the further compressionof the gas behind the piston 28 will gradually and smoothly bring thebarrel to a halt and prevent any sudden engagement of the parts, such asthe barrel striking the receiver. With the recoil absorbing mechanism ofthe present invention, the recoil can be progressively and smoothlybrought to a halt in the gun illustrated in a distance of not more 2inches.

After the recoil movement has been brought to a halt, the gas undercompression behind the piston will expand and assist the return spring12 to initiate return movement of the barrel to original position. Assoon as the passages 38 and 44 again come into registry with the slot40, however, the gas under pressure behind the piston will vent toatmosphere through the barrel, thus leaving the remaining returnmovement to the action of the relatively light spring 12. As a resultthe barrel is returned to battery with moderate velocity and decreasedshock and jar on the mechanism.

It thus will be seen that there has been provided in accordance with theinvention, a recoil absorbing mechanism for firearms which is of lightweight and simple construction and yet effective for progressivelyhalting recoil movement of the barrel member with minimum impact or kickwithout the use of heavy springs or friction devices. The mechanism isreliable and rugged in operation and may be used to provide a desiredshort recoil action and does not require adjustment for varying loads.The term barrel movable in recoil is used herein in a generic sense toinclude arrangements wherein the entire barrel moves in recoil or whereonly a part thereof such as the firing chamber portion only recoils whenthe piece is fired.

Although but one embodiment has been shown, it will be apparent to thoseskilled in the art that the invention may be applied to other automaticand semi-automatic Weapons, and that modifications may be made withoutdeparting from the spirit of the invention.

I claim:

1. In a repeating firearm, a frame, a barrel movable in recoil relativeto the frame, and a recoil absorbing mechanism interconnecting the frameand barrel comprising a cylinder fixed to the frame and a pistonslidable in said cylinder and fixedly connected to the barrel forreciprocal movement with the barrel, and means forming a gas passagewayfrom an intermediate portion of the barrel to the cylinder and means onthe cylinder for closing the passageway during final recoil movement ofthe barrel.

2. In a repeating firearm, recoil relative to the frame, nism comprisingcylinder a frame, a barrel movable in and a recoil absorbing mechameansand piston means, one

of said means being parallel to and fixedly connected to the frame andthe other of said means being parallel to and fixedly connected to thebarrel for reciprocal movement with the barrel, and means forming a gaspassageway from the cylinder to the barrel forwardly of the firingchamber of the barrel whereby combustion gases are interoduced to thecylinder after the firearm is fired, said passageway being interruptedby relative movement of the cylinder and piston prior to final recoilmovement of the barrel and while the shot is still in the barrel.

3. In a repeating firearm, a frame, a barrel movable in recoil relativeto the frame, and a recoil absorbing mechanism comprising cylinder meansand piston means, one of said means being parallel to and fixedlyconnected to the frame, and the other of said means being parallel toand fixedly connected to the barrel for reciprocal movement with thebarrel, and means on the barrel having a gas passageway extending froman intermediate portion of the barrel to the cylinder, said cylinderhaving an apertured wall for opening the passageway to permit combustiongases to enter the cylinder from the barrel during a portion of therecoil movement of the barrel after the firearm is fired and closing thepassageway during the remainder of the recoil movement of the barrel.

4. In a repeating firearm, a frame, a barrel movable in recoil relativeto the frame, and a recoil absorbing mechanism comprising a cylinderparallel to the barrel and fixed relative to the frame, a pistonslidable in said cylinder and fixedly connected to the barrel forreciprocal movement with the barrel, and a depending memher on anintermediate portion of the barrel engaging the cylinder and having apassageway extending between the barrel and cylinder, said cylinderhaving means for closing the passageway during a pre-determined portionof the final recoil movement of the barrel, and a relatively lightreturn spring for the piston and barrel.

5. In a repeating firearm, a frame, a barrel movable in recoil relativeto the frame, and a recoil absorbing mechanism comprising a cylinderparallel to the barrel and fixed to the frame, a piston slidable in thecylinder and fixedly connected to the barrel for reciprocal movementtherewith, and a guide member fixed to the barrel and slidable on thecylinder having a passageway extending from an intermediate portion ofthe barrel to the cylinder, said cylinder having an elongated slotregistering with said passageway only during a portion of the recoilmovement of the barrel.

6. In a repeating firearm, a frame, a barrel movable in recoilrearwardly of the frame, and means for braking recoil of the barrelcomprising an air cylinder parallel to said barrel and fixed relative tothe frame, a piston slidable in said cylinder and operatively connectedto said barrel for reciprocal movement with the barrel, said cylinderhaving a slot aperture extending parallel to said barrel and adjacentthereto, and means forming a passageway from an intermediate portion ofthe barrel and having a discharge port positioned for registry with saidslot aperture, said piston having a passage therethrough with one end atthe rear face of the piston and with the other end of the passagepositioned for registry with said slot aperture and in registry withsaid discharge port,

said port and passage being registrable with said slot during a part ofthe recoil movement of the barrel to permit passage of powder gases intothe cylinder.

7. In a repeating firearm, a frame, a barrel movable in recoilrearwardly of the frame, and means for braking recoil of the barrelcomprising a cylinder fixedly mounted on said frame parallel to saidbarrel, a guide ring fixed to the barrel and slidably mounted on saidcylinder, a piston slidable in said cylinder, means connecting thepiston to the guide ring of the'barrel to provide for simultaneousreciprocal movement of the piston and barrel, the wall of said cylinderhaving an elongated slot aperture parallel to the axis thereof, saidguide ring having a passageway communicating with an intermediateportion of the barrel and having a gas discharge port positioned forregistry with said slot aperture, said piston having a gas passagetherein with one end of the passage opening at the rear face of thepiston and with the other end of the passage in registry with said portand positioned for registry with said slot aperture, the port and saidother end of the gas passage being in registry with the slot apertureduring a portion of the rearward recoil of the barrel for passage ofgases therethrough into the cylinder and being closed by the wall of thecylinder during final recoil movement of the barrel.

8. In a repeating firearm, a frame, a barrel movable in recoilrearwardly of the frame, an assembly for braking recoil of the barreland returning the barrel to battery comprising a tube fixedly mounted onthe frame and disposed below and parallel to the barrel, a downwardlydepending guide ring on the barrel at about midlength thereof slidablyengaged with the tube, a piston slidably mounted in said tube, meansconnecting the piston to the guide ring of the barrel for simultaneousreciprocal movement of the piston with the barrel, 2. fixed wall in saidtube rearwardly of said piston defining an air cylinder in combinationtherewith, said guide ring having a gas port extending downwardlytherethrough, said tube having an elongated slot in the upper portionthereof extending parallel to the barrel and positioned for registrywith said gas port, said piston having a gas passageway with one end ofthe passageway opening into said cylinder at the rear face of the pistonand with the other end of the passageway positioned for registry withthe said slot and in registry with said gas port, and light compressionspring means biasing the barrel and guide ring forwardly, the port andsaid other end of the passageway being in registry with said slot for aportion of the recoil movement of the barrel to conduct gases from thebarrel tothe air cylinder and moving beyond the slot during final recoilmovement of the barrel, the gases admitted to said cylinder beingcompressed by the rearward movement of the piston and thereby brakingsuch movement.

References Cited in the file of this patent UNITED STATES PATENTS955,796 Haussner Apr. 19, 1910 2,372,542 Bloomquist Mar. 27, 19452,409,225 Schaich Oct. 15, 1946 2,800,059 Miller July 23, 1957 FOREIGNPATENTS 321,922 Switzerland July 15, 1957

